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1.
Wiad Lek ; 74(7): 1587-1594, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34459756

RESUMO

OBJECTIVE: The aim: The study aimed to assess the content of selected toxic compounds in mineral and spring waters available on the Polish market regarding potential health risks to consumers. PATIENTS AND METHODS: Materials and methods: Selected mineral and spring waters available on the Polish market were the study's objects. The content of such chemical compounds as arsenic, cadmium, lead, copper, and mercury in selected mineral and spring waters was analyzed. The content of metals in the samples was determined by inductively coupled plasma mass spectrometry (ICP-MS). Additionally, a literature review was performed to determine nitrates contamination of bottled waters available on the Polish market. Based on the collected data, an assessment of exposure and health risk to consumers was performed. RESULTS: Results: Arsenic had the highest mean concentration in the analyzed water samples. Consumption of such contaminated waters may be a significant health risk factor for consumers. Literature data indicate a relatively low content of nitrates in bottled waters available on the Polish market. Consumption of such mineral waters is not a significant source of exposure and does not translate into a significant health risk for consumers. CONCLUSION: Conclusions: To ensure consumers' health safety, there is a need to monitor the content of potentially harmful compounds in mineral and spring waters available on the Polish market.


Assuntos
Arsênio , Água Potável , Mercúrio , Águas Minerais , Arsênio/análise , Arsênio/toxicidade , Humanos , Minerais
2.
Molecules ; 26(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34279418

RESUMO

The thermodynamic properties of phenacetin in solid state and in saturated conditions in neat and binary solvents were characterized based on differential scanning calorimetry and spectroscopic solubility measurements. The temperature-related heat capacity values measured for both the solid and melt states were provided and used for precise determination of the values for ideal solubility, fusion thermodynamic functions, and activity coefficients in the studied solutions. Factors affecting the accuracy of these values were discussed in terms of various models of specific heat capacity difference for phenacetin in crystal and super-cooled liquid states. It was concluded that different properties have varying sensitivity in relation to the accuracy of heat capacity values. The values of temperature-related excess solubility in aqueous binary mixtures were interpreted using the Jouyban-Acree solubility equation for aqueous binary mixtures of methanol, DMSO, DMF, 1,4-dioxane, and acetonitrile. All binary solvent systems studied exhibited strong positive non-ideal deviations from an algebraic rule of mixing. Additionally, an interesting co-solvency phenomenon was observed with phenacetin solubility in aqueous mixtures with acetonitrile or 1,4-dioxane. The remaining three solvents acted as strong co-solvents.


Assuntos
Fenacetina/química , Solventes/química , Água/química , Fenômenos Físicos , Solubilidade , Temperatura , Termodinâmica
3.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298985

RESUMO

In this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential scanning calorimetry was used to characterize the fusion thermodynamics of nicotinamide. In particular, the heat capacity change upon melting was measured. The experimental data were interpreted by means of COSMO-RS-DARE (conductor-like screening model for realistic solvation-dimerization, aggregation, and reaction extension) for concentration dependent reactions. The solute-solute and solute-solvent intermolecular interactions were found to be significant in all of the studied systems, which was proven by the computed mutual affinity of the components at the saturated conditions. The values of the Gibbs free energies of pair formation were derived at an advanced level of theory (MP2), including corrections for electron correlation and zero point vibrational energy (ZPE). In all of the studied systems the self-association of nicotinamide was found to be a predominant intermolecular complex, irrespective of the temperature and composition of the binary system. The application of the COSMO-RS-DARE approach led to a perfect match between the computed and measured solubility data, by optimizing the parameter of intermolecular interactions.


Assuntos
Niacinamida/química , Termodinâmica , Acetonitrilas , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Dimerização , Dimetil Sulfóxido , Dimetilformamida , Dioxanos , Metanol , Modelos Químicos , Concentração Osmolar , Solubilidade , Soluções , Solventes , Espectrofotometria Infravermelho , Temperatura , Vibração , Água
4.
J Oral Pathol Med ; 50(1): 22-31, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33231892

RESUMO

OBJECTIVES: The purpose of this meta-analysis was to reveal a potential association of the four functional polymorphisms in human Beta-defensin 1 (DEFB1) gene: rs1047031(c*5G > A) at 3'UTR and rs11362 (-20 G > A), rs1800972(-44 C > G), and rs1799946 (-52 G > A) at 5'UTR with the risk of common oral cavity pathologies that included periodontitis, caries, lichen planus, and recurrent aphthous stomatitis. METHODS: The relevant studies were obtained by the two researchers from PubMed, Scopus, and Web of Science up to April 29, 2020. The manual search of the reference lists was also performed. Studies on DEFB1 gene polymorphisms and oral cavity disorders, using the case-control genetic association analysis approach, and published as full texts in English were included. To assess the association strength, odds ratios (ORs) with their 95% confidence intervals (CIs) were extracted. RESULTS: Thirteen publications met the inclusion criteria and were incorporated in this meta-analysis. Statistically significant values of the association tests were found only for the rs1047031 polymorphism. Allele distribution in the rs1047031 polymorphism was significantly associated with susceptibility to oral cavity pathologies (adjusted P value = 0.003). The rare variant allele carriers had a significantly higher risk for oral disasters under recessive (CC vs CT + TT), and CC vs CT models. No significant correlations between rs11362, rs1800972, and rs1799946 and the risk of oral pathologies were revealed. CONCLUSIONS: Significant association between rs1047031 polymorphism and risk of oral pathologies has been found, and therefore, we suggest to include this polymorphism in future research concerning the genetic background of the oral cavity diseases.


Assuntos
beta-Defensinas , Alelos , Predisposição Genética para Doença/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , beta-Defensinas/genética
5.
Mol Ecol Resour ; 20(6): 1486-1504, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32516485

RESUMO

DNA metabarcoding offers new perspectives, especially with regard to the high-throughput identification and diagnostics of pathogens. Microsporidia are an example of widely distributed, opportunistic and pathogenic microorganisms in which molecular identification is important for both environmental research and clinical diagnostics. We have developed a method for parallel detection of both microsporidian infection and the host species. We designed new primer sets: one specific for the classical Microsporidia (targeting the hypervariable V5 region of small subunit [ssu] rDNA), and a second one targeting a shortened fragment of the COI gene (standard metazoan DNA-barcode); both markers are well suited for next generation sequencing. Analysis of the ssu rDNA data set representing 607 microsporidian species (120 genera) indicated that the V5 region enables identification of >98% species in the data set (596/607). To test the method, we used microsporidians that infect mosquitoes in natural populations. Using mini-COI data, all field-collected mosquitoes were unambiguously assigned to seven species; among them almost 60% of specimens were positive for at least 11 different microsporidian species, including a new microsporidian ssu rDNA sequence (Microsporidium sp. PL01). Phylogenetic analysis showed that this species belongs to one of the two main clades in the Terresporidia. We found a high rate of microsporidian co-infections (9.4%). The numbers of sequence reads for the operational taxonomic units suggest that the occurrence of Nosema spp. in co-infections could benefit them; however, this observation should be retested using a more intensive host sampling. Our results show that DNA barcoding is a rapid and cost-effective method for deciphering sample diversity in greater resolution, including the hidden biodiversity that may be overlooked using classical methodology.

6.
Materials (Basel) ; 13(3)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32024146

RESUMO

Hot-mix asphalt (HMA) remains the predominant material for pavement surfacing. Mixing is performed at about 180 °C, depending on the bitumen used. Environmental concerns in terms of emissions and energy demand are fostering new sustainable technologies in road construction. Warm-mix asphalt (WMA) and half-warm-mix asphalt (HWMA) mixtures meet current expectations in that they are produced at lower temperatures, 100-130 °C, ensured by foaming the bitumen with water. The extent of temperature reduction requires that the mixture has adequate moisture and frost resistance, which is particularly important in countries that have a low-temperature climate. Asphalt concrete AC 8 S with 50/70-grade foamed bitumen modified with 0.6 wt.% surface-active agent (SAA) was used in the tests. To provide the AC mixture with the required resistance to climatic factors (water, temperature below 0), hydrated lime was added at 0, 15, 30, and 45 wt.% as limestone filler replacement. The influence of the hydrated lime addition on the air void content and resistance to moisture and frost damage was investigated according to the WT-2 2014 methodology based on EN 12697-12: 2008 and to the modified AASHTO T283 method. The optimum content of hydrated lime for filler replacement was determined through statistical analysis of the test results. With the optimum hydrated lime replacement of 30%, the required level of moisture and frost resistance of HWMA concrete with foamed bitumen is achieved. The results of this study confirmed the suitability of HWMA concrete with foamed bitumen for application in road construction practice.

7.
Materials (Basel) ; 13(2)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940940

RESUMO

The paper aimed at assessing the feasibility of using natural zeolites as a mineral filler substitute for asphalt mixtures produced at around 120 °C temperatures with a water foamed binder and compacted at 100 °C. The tests utilized the AC 16 asphalt concrete mixture intended for the binder and base course with the mineral filler fraction amounting to 4% by wt. comprising limestone dust and zeolites (when added). A reference hot mix and warm mix with foamed bitumen were compared to two mixes with zeolites, with one containing 0.4% of a water-modified (20% moisture content) zeolite and the second containing 1.0% of natural air-dried zeolite. The investigations included: assessment of campactability using a gyratory compactor, air void content, indirect tensile strength before and after conditioning with one freeze-thaw cycle, and the resulting resistance to moisture and frost damage. The mixtures with zeolites exhibited decreased compactability when compared to reference mixes, which the Marshall samples confirmed. The mechanical properties have also deteriorated in zeolite-bearing mixtures, which was partially accounted to the decreased compaction level. It was concluded that the temperature of the mixture production was too low for the zeolite water to significantly improve the compactablity of the asphalt mixture and its mechanical parameters.

8.
Materials (Basel) ; 12(21)2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31717740

RESUMO

To ensure the standard properties of half-warm asphalt (HWA) mixes produced with foamed bitumen, the binder needs to have the best possible characteristics. One way to attain this is to modify the bitumen before it is foamed. The 50/70 penetration bitumen used in this study, was modified with a surface active agent (SAA) at different rates (0.2%, 0.4%, and 0.6% by wt.). The effect of the modifier on the bitumen properties (penetration, softening point, the Fraass breaking point, dynamic viscosity at 60 °C, 90 °C, and 135 °C) and on the binder foaming parameters (expansion ratio - ER, half-life - HL, foam index - FI) was investigated and the optimum quantity of foaming water was determined. Statistical analysis of the results showed that the addition of 0.6% SAA had the most beneficial effect on the set of 50/70 bitumen standard properties and foaming characteristics.

9.
J Sep Sci ; 42(16): 2628-2639, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31168923

RESUMO

Liquid chromatography coupled to spectrophotometric detection of new antiepileptic compounds, 1,2,4-triazole-3-thione derivatives, on immobilized artificial membrane phosphatidylcholine is reported. The curves representing the relationship between ln k versus 1/T generated under isocratic conditions by the use of methanol and acetonitrile-containing eluent systems have been constructed in order to determine the thermodynamic parameters: the enthalpies, entropies and the relative free energies. The hydrocarbon chains of analytes significantly influenced the membrane behavior of the whole molecules. Excellent correlations of the theoretical lipophilicity with the experimental thermodynamic descriptors, have confirmed contribution of the hydrophobic interactions in the retention process. However, presence of sulfur or oxygen as heteroatoms at R1 substituents in the 1,2,4-triazole ring appears to be responsible for more pronounced selectivity of these compounds on the phosphatidylcholine stationary phase. Molecular dynamics simulations revealed the selective preferences of the phosphatidylcholine with respect to the compounds with either ether of sulfide moieties. Experimental and theoretical set-ups resulted in corresponding outcomes.


Assuntos
Materiais Biomiméticos/química , Varredura Diferencial de Calorimetria , Fosfatidilcolinas/química , Termodinâmica , Tionas/análise , Triazóis/análise , Cromatografia Líquida , Estrutura Molecular , Espectrofotometria
10.
Arch Oral Biol ; 101: 130-134, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30928860

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the possible association between two single nucleotide polymorphisms of the ß-defensin 1 gene: -20 G > A and -44 C > G at 5 untranslated region and recurrent aphthous stomatitis in a cohort of Polish patients. DESIGN: One hundred and six patients suffering from recurrent aphthous stomatitis and 96 healthy volunteers were genotyped at ß-defensin 1-20 G > A and -44 C > G using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. The results were statistically analysed with the difference test between two proportion and chi-square tests with p < 0.05 as a significance level (Dell Statistica data analysis software system, version 13, Dell Inc. 2016). RESULTS: No statistically significant differences between the tested groups were revealed in the genotype distribution for -20 G > A and -44 C > G polymorphisms of the ß-defensin 1 gene. Stratification into carriers and non-carriers of alleles did not unequivocally show the single nucleotide polymorphism recognized as a risk factor for recurrent aphthous stomatitis. However, after gender stratification, statistically significant differences in the distribution of some DEFB1 genotypes were observed. Heterozygotes of G[-20]A and C[-44]G genotypes were found more frequently in males with RAS than in males from the control group. Moreover, a significantly higher rate of carriers of the polymorphic *A[-20] allele was found in males with RAS compared to the controls. CONCLUSIONS: The role of the tested single nucleotide polymorphisms of the ß-defensin 1 gene in the aetiology of recurrent aphthous stomatitis has not been confirmed. Further observations are required to clarify this potential association.


Assuntos
Regiões 5' não Traduzidas , Estomatite Aftosa/genética , beta-Defensinas/genética , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Polônia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único
11.
Biomark Med ; 13(7): 523-534, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30854869

RESUMO

Aim: To assess the diagnostic value of selected miRNAs from various material collected from hepatocellular carcinoma (HCC) patients. Patients & methods: Tissue, serum, urine and fecal samples from HCC patients and healthy individuals were screened for associated miRNAs using microarray analysis; the selected miRNAs were then validated by real time-quantitative PCR on 65 patients. Results: Serum miR-122, a combination of serum miR-155 with miR-885-5p, a combination of urinary miR-532-3p with miR-765, and fecal miR-320a displayed 100% efficiency in discriminating patients from controls. A combination of urinary miR-532-3p and miR-765 allowed patients with neoplastic grade G3 to be distinguished from those with G1 and G2. Conclusion: Additionally to serum, urine and feces also appeared to be valuable source of potential HCC noninvasive miRNA biomarkers.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/urina , Estudos de Casos e Controles , Fezes/química , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/urina , Masculino , MicroRNAs/sangue , MicroRNAs/urina , Análise de Sobrevida
12.
Food Chem ; 284: 264-269, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744856

RESUMO

The aim of this study was to determine the content of ochratoxin A (OTA) using high-performance liquid chromatography (HPLC) in selected food products, in the aspect of consumer health hazards. In the study 473 samples of food products, available on the Silesia market in Poland, were analyzed. For the determination of ochratoxin A in food, high performance liquid chromatography (HPLC) with fluorescence detection was used. Almost 22% of the samples were contaminated with ochratoxin A. The highest concentration of OTA was determined in raisins (34.0 µg/kg), which exceeds the permissible level 3.5 times. In one of the analyzed rye flour samples ochratoxin A was determined at level 19.5 µg/kg, where the maximum level is 3 µg/kg. For the general population, there is a risk of exposure to ochratoxin A from food, which justifies the need to monitor the quality of products for mycotoxin contamination.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ocratoxinas/análise , Vitis/química , Exposição Dietética , Farinha/análise , Humanos , Polônia , Medição de Risco , Espectrometria de Fluorescência , Vitis/metabolismo
13.
Eng Life Sci ; 19(8): 557-574, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32625032

RESUMO

Biosynthesis of metabolites and enzymes by filamentous fungi depends on their morphological form in submerged cultures. However, their early stages of growth lasting approximately 24 h, from the introduction of spores to the medium until the formation of stable morphological forms, such as clumps or pellets, have rarely been the objects of experimental and modeling studies. Microparticle-enhanced cultivation (MPEC) has been applied only to a few fungal species, mainly Aspergilli. Therefore, the objective of this work was to formulate the kinetic model to describe the early stages of the fungal evolution in the standard cultivation and MPEC for Aspergillus terreus, Chaetomium globosum, Penicillium rubens, and Mucor racemosus. These fungi exhibit various mechanisms of agglomerates formation in submerged cultures. The experiments were performed in batch shake flasks (parameters identification) and a stirred tank bioreactor (model verification). In the balance equation for fungal cells, the mean projected area of hyphal objects measured by the digital analysis of microscopic images was used as the dependent variable. The analysis of the experimental data and model solution revealed that the effect of the microparticles (aluminum oxide at 6 g L-1) in MPEC toward the studied filamentous fungi was to the high extent species dependent. This effect was most evident in the case of spore coagulative A. terreus and noncoagulative M. racemosus.

14.
Connect Tissue Res ; 60(1): 29-39, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30231645

RESUMO

PURPOSE: Investigate the content of fibrotic fibrils in gingival tissue and the proliferation of fibroblasts collected from recurrent and non-recurrent hereditary gingival fibromatosis (HGF) and idiopathic gingival fibromatosis (IGF). METHODS: Gingival biopsies were collected from HGF (n = 3) and IGF (n = 3) donors with recurrent and non-recurrent gingival overgrowths and from a control group (Ctrl, n = 3). Hematoxylin staining was performed to evaluate the histomorphology of gingival tissue. Heidenhain's AZAN trichrome staining served for visualization of fibrotic fibrils in gingiva. Quantitative analysis of the content of fibrotic fibrils in gingival tissue was performed using a polarized light microscope. Proliferation was evaluated at 24 h, 48 h, and 72 h in fibroblast cultures using a cell proliferation ELISA assay based on 5-bromo-2'-deoxyuridine (BrdU). RESULTS: Numerous blood vessels and fibroblasts were observed in recurrent overgrowths, whereas moderate blood vessels and moderate to scanty fibroblasts were detected in non-recurrent overgrowths. Heidenhain's staining revealed numerous collagen fibers in both recurrent and non-recurrent overgrowths. Quantitative analysis in a polarizing microscope showed significant accumulation of fibrotic fibrils exclusively in the overgrowths with the recurrence. In all time-points, increased proliferation of cells from all recurrent overgrowths was observed, but not from overgrowths which do not reoccur. CONCLUSIONS: The study revealed that recurrent gingival overgrowths consist of highly fibrotic and dense connective tissue with numerous blood vessels and abundant fibroblasts. We also demonstrated that unlike fibroblasts derived from overgrowths, which did not present recurrence, fibroblasts derived from highly fibrotic and recurrent overgrowths maintain high rate of proliferation in vitro.


Assuntos
Fibroblastos/patologia , Fibromatose Gengival/patologia , Adolescente , Adulto , Proliferação de Células , Células Cultivadas , Criança , Feminino , Fibrose , Gengiva/patologia , Humanos
15.
J Sep Sci ; 41(15): 3129-3142, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29897661

RESUMO

Spinacia oleracea L. extract was immobilized on an octadecyl-bonded silica surface to produce a new sorbent for the solid-phase extraction of trace amounts of metal ions from aqueous neutral samples. A measurement of the metal content has been performed by using graphite furnace atomic absorption spectroscopy. The affinity of the investigated bivalent metal cations for the modified sorbent are in the order: Pb(II) > Cu(II) > Ni(II) > Zn(II) ≈ Cd(II) ≈ Co(II). The quantum-chemically calculated chlorophyll-a-metal ion binding energies were consistent with the measured affinities of the corresponding metal ions to the investigated sorbent. The maximum sorption capacity obtained for Pb(II) was equal to 1.44 µmol/g. The value of lead uptake was significantly higher in comparison to the one reported for other sorbents and biosorbents. Immobilized chlorophyll a is responsible for a chelation process with stoichiometry 1:1 owing to the porphyrin rings, which was confirmed by the quantitative analysis performed by reversed-phase high-performance liquid chromatography with diode array detection. The Toth adsorption isotherm model was applicable to the description of the adsorption process of either chlorophyll a or Pb(II). The structural analysis of sorbent was done using Fourier-transform Raman spectroscopy and scanning electron microscopy with an energy dispersive X-ray detector.


Assuntos
Chumbo/isolamento & purificação , Pigmentos Biológicos/química , Dióxido de Silício/química , Extração em Fase Sólida , Spinacia oleracea/química , Poluentes Químicos da Água/química , Chumbo/química , Processos Fotoquímicos , Fotossíntese , Pigmentos Biológicos/síntese química
16.
Microbiologyopen ; 7(5): e00603, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29504287

RESUMO

The application of microparticle-enhanced cultivation (MPEC) is an attractive method to control mycelial morphology, and thus enhance the production of metabolites and enzymes in the submerged cultivations of filamentous fungi. Unfortunately, most literature data deals with the spore-agglomerating species like aspergilli. Therefore, the detailed quantitative study of the morphological evolution of four different fungal species (Aspergillus terreus, Penicillium rubens, Chaetomium globosum, and Mucor racemosus) based on the digital analysis of microscopic images was presented in this paper. In accordance with the current knowledge, these species exhibit different mechanisms of agglomerates formation. The standard submerged shake flask cultivations (as a reference) and MPEC involving 10 µm aluminum oxide microparticles (6 g·L-1 ) were performed. The morphological parameters, including mean projected area, elongation, roughness, and morphology number were determined for the mycelial objects within the first 24 hr of growth. It occurred that heretofore observed and widely discussed effect of microparticles on fungi, namely the decrease in pellet size, was not observed for the species whose pellet formation mechanism is different from spore agglomeration. In the MPEC, C. globosum developed core-shell pellets, and M. racemosus, a nonagglomerative species, formed the relatively larger, compared to standard cultures, pellets with distinct cores.


Assuntos
Óxido de Alumínio/metabolismo , Aspergillus/crescimento & desenvolvimento , Chaetomium/crescimento & desenvolvimento , Mucor/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Aspergillus/efeitos dos fármacos , Adesão Celular , Chaetomium/efeitos dos fármacos , Microscopia , Mucor/efeitos dos fármacos , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Penicillium/efeitos dos fármacos
17.
Toxicol In Vitro ; 47: 8-17, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29107684

RESUMO

Although methacrylic acid derivatives in their polymeric form are considered to be safe, insufficient polymerization and the release of monomers due to either mechanical or enzymatical factors can lead to their reaching millimolar concentrations in local tissue. The present study evaluates the effect of two methacrylate monomers - ethylene glycol dimethacrylate (EGDMA) and diethylene glycol dimethacrylate (DEGDMA) - on human gingival fibroblasts (HGFs). Both monomers were found to reduce cells viability in MTT assay, increase apoptosis and cause cell cycle arrest in G1/G0 phase. They also increased intracellular reactive oxygen species (ROS) production as measured by DCFH-DA and DHE probes and increased expression of GPx4 and SOD2. Both monomers increased DNA damage in comet assay. Moreover, HGFs were not able to repair those lesions within 120min of repair incubation. However, the monomers were not found to have any effect on the integrity of isolated plasmids. We postulate that EGDMA and DEGDMA exhibit their cytotoxic and genotoxic properties via increased production of ROS, which cause DNA damage, affect apoptosis, viability and cell cycle. Further studies are needed to better understand the properties of methacrylic acid monomers and to evaluate the risk that they cause for patients, dentists and dental technicians.


Assuntos
Apoptose/efeitos dos fármacos , Reagentes para Ligações Cruzadas/toxicidade , Reparo do DNA/efeitos dos fármacos , Etilenoglicóis/toxicidade , Gengiva/efeitos dos fármacos , Metacrilatos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ensaio Cometa , Dano ao DNA , Materiais Dentários/toxicidade , Indução Enzimática/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Gengiva/citologia , Gengiva/metabolismo , Glutationa Peroxidase/química , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Humanos , Concentração Osmolar , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Plasmídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/química , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-29100761

RESUMO

The new sorbent for solid phase extraction (SPE), based on silica gel modified with a copper (II), was obtained and its application for phospholipids removal from the human plasma was tested. SPE column conditioning requirements, the volume of the plasma, the composition of the elution solvent were all established. The efficacy of the removal of phospholipids was compared for different methods such as standard protein precipitation or HybridSPE Phospholipid Ultra and HybridSPE-PPT. The sample clean-up was verified by mass spectrometry (MS) and by monitoring of chromatograms in the region between 190nm and 400nm. The Fourier Transform Infrared Spectroscopy FT-IR and confocal Raman microscopy were used to evaluating the silica gel modifications and to show the structure of lipids confined in the silica pores.


Assuntos
Fosfolipídeos/sangue , Fosfolipídeos/isolamento & purificação , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Cobre/química , Humanos , Espectrometria de Massas , Sílica Gel/química
19.
J Sep Sci ; 40(21): 4176-4190, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28869783

RESUMO

Basic thermodynamic functions responsible for retention of new 1,2,4-triazole derivatives exhibiting varied antiepileptic activity on cholesterol-based stationary phase were determined. Evaluation of the Gibbs energy change, the change in enthalpy and the change in entropy was based on the van't Hoff relationship representing lnk versus 1/T. A detailed discussion of the van't Hoff equation, exploring the influence of the phase ratio on deviations from linearity in a van't Hoff plot is presented. We show chromatographic evidence to the question of how a varied mobile phase composition may cause different thermodynamic phase ratios. The analysis of data from a differential scanning calorimetry excluded any phase transitions of either the individual solutes or cholesterol stationary phase suspended in the mobile phase components within the studied temperature range.


Assuntos
Anticonvulsivantes/análise , Cromatografia Líquida de Alta Pressão , Acetonitrilas , Colesterol , Metanol , Temperatura , Termodinâmica , Água
20.
Arch Oral Biol ; 84: 45-49, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28942153

RESUMO

OBJECTIVES: Recurrent aphthous stomatitis (RAS) is a chronic, ulcerative disease with a probable polygenic mode of inheritance and complex etiology with a strong immunological background. The aim of the present study was to determine the possible association between two single nucleotide polymorphisms (SNPs) of the IL-1ß gene: IL-1ß-511 T>C (rs16944) and IL-1ß+3954C>T (rs1143634) and RAS susceptibility in a moderately large group of patients. DESIGN: One hundred and four patients with minor, major and herpetiform RAS and 75 healthy volunteers were genotyped at IL-1ß-511 T>C (rs16944) and IL-1ß+3954C>T (rs1143634) using the PCR-RFLP approach. The results were statistically analysed with chi-square test and test of difference between two rates of structure, with p<0.05 assumed to be a statistically significance level (Statistica 10, StatSoft®, Kraków, Poland). RESULTS: There were no statistically significant differences in the genotype distribution for the IL-1ß C[+3954]T polymorphism between the RAS and control groups. The frequency of IL-1ß*T[-511]/*T[-511] homozygotes among the patients was significantly higher when compared to our study control (p<0.0347). The results after stratification into carriers and non-carriers of C and T alleles did not clearly indicate which SNP may be considered a risk factor for RAS. CONCLUSIONS: The genetic association between the studied SNPs of the IL-1ß gene and RAS remains controversial and requires further investigation.


Assuntos
Interleucina-1beta/genética , Polimorfismo de Nucleotídeo Único , Estomatite Aftosa/genética , Alelos , Feminino , Genótipo , Homozigoto , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Recidiva
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